package com.walmartlabs.concord.agent.cfg;

/*-
 * *****
 * Concord
 * -----
 * Copyright (C) 2017 - 2019 Walmart Inc.
 * -----
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * =====
 */

import com.typesafe.config.Config;
import com.walmartlabs.concord.common.IOUtils;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.function.Supplier;

public final class Utils {

    public static String getStringOrDefault(Config cfg, String key, Supplier<String> defaultValueSupplier) {
        if (cfg.hasPath(key)) {
            return cfg.getString(key);
        }
        return defaultValueSupplier.get();
    }

    public static Path getOptionalAbsolutePath(Config cfg, String key) {
        if (!cfg.hasPath(key)) {
            return null;
        }

        String s = cfg.getString(key).trim();
        if (s.isEmpty()) {
            return null;
        }

        if (!s.startsWith("/")) {
            throw new IllegalArgumentException(key + " must be an absolute path, got: " + s);
        }

        return Paths.get(s);
    }

    public static Path getOrCreatePath(Config cfg, String key) {
        try {
            if (!cfg.hasPath(key)) {
                return IOUtils.createTempDir(key);
            }

            String value = cfg.getString(key);
            if (value.startsWith("/")) {
                Path p = Paths.get(value)
                        .normalize()
                        .toAbsolutePath();

                if (!Files.exists(p)) {
                    Files.createDirectories(p);
                }

                return p;
            }
            return IOUtils.createTempDir(value);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    private Utils() {
    }
}
